Name Theory_2914-4749516-23_1
Workunit 232871820
Created 6 Jun 2025, 10:26:31 UTC
Sent 6 Jun 2025, 14:21:39 UTC
Report deadline 17 Jun 2025, 14:21:39 UTC
Received 6 Jun 2025, 15:22:42 UTC
Server state Over
Outcome Computation error
Client state Compute error
Exit status 1 (0x00000001) Unknown error code
Computer ID 10824038
Run time 19 sec
CPU time
Validate state Invalid
Credit 0.00
Device peak FLOPS 4.59 GFLOPS
Application version Theory Simulation v300.95 (vbox64_theory)
windows_x86_64
Peak working set size 11.24 MB
Peak swap size 6.24 MB
Peak disk usage 1.09 MB

Stderr output

<core_client_version>8.0.2</core_client_version>
<![CDATA[
<message>
Fonction incorrecte.
 (0x1) - exit code 1 (0x1)</message>
<stderr_txt>
2025-06-06 16:21:42 (14460): vboxwrapper version 26210
2025-06-06 16:21:42 (14460): BOINC client version: 8.0.2
2025-06-06 16:21:43 (14460): Detected: VirtualBox VboxManage Interface (Version: 7.0.6)
2025-06-06 16:21:43 (14460): Detected: Heartbeat check (file: 'heartbeat' every 1800.000000 seconds)
2025-06-06 16:21:44 (14460): Successfully copied 'init_data.xml' to the shared directory.
2025-06-06 16:21:44 (14460): Successfully copied 'input' to the shared directory.
2025-06-06 16:21:44 (14460): Create VM. (boinc_05000aedbde784d5, slot#0)
2025-06-06 16:21:44 (14460): Setting Memory Size for VM. (630MB)
2025-06-06 16:21:45 (14460): Setting CPU Count for VM. (1)
2025-06-06 16:21:45 (14460): Setting Chipset Options for VM.
2025-06-06 16:21:45 (14460): Setting Graphics Controller Options for VM. (Driver: VBoxVGA, 16MB)
2025-06-06 16:21:45 (14460): Setting Boot Options for VM.
2025-06-06 16:21:46 (14460): Setting Network Configuration for NAT. (Driver: virtio)
2025-06-06 16:21:46 (14460): Enabling VM Network Access.
2025-06-06 16:21:47 (14460): Disabling USB Support for VM.
2025-06-06 16:21:47 (14460): Disabling COM Port Support for VM.
2025-06-06 16:21:47 (14460): Disabling LPT Port Support for VM.
2025-06-06 16:21:47 (14460): Disabling Audio Support for VM.
2025-06-06 16:21:48 (14460): Disabling Clipboard Support for VM.
2025-06-06 16:21:48 (14460): Disabling Drag and Drop Support for VM.
2025-06-06 16:21:48 (14460): Adding storage controller(s) to VM.
2025-06-06 16:21:48 (14460): Adding virtual disk drive to VM. (Theory_2025_04_17_prod.vdi)
2025-06-06 16:21:51 (14460): Adding VirtualBox Guest Additions to VM.
2025-06-06 16:21:51 (14460): Adding network bandwidth throttle group to VM. (Defaulting to 1024GB)
2025-06-06 16:21:51 (14460): forwarding host port 62155 to guest port 80
2025-06-06 16:21:51 (14460): Enabling remote desktop for VM.
2025-06-06 16:21:52 (14460): Required extension pack not installed, remote desktop not enabled.
2025-06-06 16:21:52 (14460): Enabling shared directory for VM.
2025-06-06 16:21:52 (14460): Starting VM using VBoxManage interface. (boinc_05000aedbde784d5, slot#0)
2025-06-06 16:21:53 (14460): Error in start VM for VM: 1
Command:
VBoxManage -q startvm "boinc_05000aedbde784d5" --type headless
Output:
VBoxManage.exe: error: The virtual machine 'boinc_05000aedbde784d5' has terminated unexpectedly during startup with exit code 1 (0x1).  More details may be available in 'C:\ProgramData\BOINC\slots\0\boinc_05000aedbde784d5\Logs\VBoxHardening.log'
VBoxManage.exe: error: Details: code E_FAIL (0x80004005), component MachineWrap, interface IMachine
Waiting for VM "boinc_05000aedbde784d5" to power on...

2025-06-06 16:21:53 (14460): VM failed to start.
2025-06-06 16:21:53 (14460): Could not start 
2025-06-06 16:21:53 (14460): ERROR: VM failed to start
2025-06-06 16:21:53 (14460): Powering off VM.
2025-06-06 16:21:53 (14460): Deregistering VM. (boinc_05000aedbde784d5, slot#0)
2025-06-06 16:21:54 (14460): Removing network bandwidth throttle group from VM.
2025-06-06 16:21:54 (14460): Removing VM from VirtualBox.

    Hypervisor System Log:

00:00:07.984100          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:07.984239          Saving settings file "C:\Users\g.morange\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:07.986787          Finished saving settings file "C:\Users\g.morange\.VirtualBox\VirtualBox.xml"
00:00:07.987032          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:07.987130          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:07.987260          Saving settings file "C:\Users\g.morange\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:07.989775          Finished saving settings file "C:\Users\g.morange\.VirtualBox\VirtualBox.xml"
00:00:07.990177          Saving settings file "C:\ProgramData\BOINC\slots\0\boinc_05000aedbde784d5\boinc_05000aedbde784d5.vbox" with version "1.19-windows"
00:00:07.992896          Finished saving settings file "C:\ProgramData\BOINC\slots\0\boinc_05000aedbde784d5\boinc_05000aedbde784d5.vbox"
00:00:08.245056          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:08.247674          Saving settings file "C:\ProgramData\BOINC\slots\0\boinc_05000aedbde784d5\boinc_05000aedbde784d5.vbox" with version "1.19-windows"
00:00:08.250735          Finished saving settings file "C:\ProgramData\BOINC\slots\0\boinc_05000aedbde784d5\boinc_05000aedbde784d5.vbox"
00:00:08.526797          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:08.530248          Saving settings file "C:\ProgramData\BOINC\slots\0\boinc_05000aedbde784d5\boinc_05000aedbde784d5.vbox" with version "1.19-windows"
00:00:08.533702          Finished saving settings file "C:\ProgramData\BOINC\slots\0\boinc_05000aedbde784d5\boinc_05000aedbde784d5.vbox"
00:00:09.066253          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:09.068679          Saving settings file "C:\ProgramData\BOINC\slots\0\boinc_05000aedbde784d5\boinc_05000aedbde784d5.vbox" with version "1.19-windows"
00:00:09.071665          Finished saving settings file "C:\ProgramData\BOINC\slots\0\boinc_05000aedbde784d5\boinc_05000aedbde784d5.vbox"
00:00:09.340613          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:09.342852          ERROR [COM]: aRC=VBOX_E_OBJECT_NOT_FOUND (0x80bb0001) aIID={7682d5eb-f00e-44f1-8ca2-99d08b1cd607} aComponent={VirtualBoxWrap} aText={&#197;&#131;o extension pack providing a cryptographic support module could be found}, preserve=false aResultDetail=0
00:00:09.347876          ERROR [COM]: aRC=VBOX_E_OBJECT_NOT_FOUND (0x80bb0001) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={SessionMachine} aText={No storage device attached to device slot 0 on port 2 of controller 'Hard Disk Controller'}, preserve=false aResultDetail=0
00:00:09.348067          ERROR [COM]: aRC=VBOX_E_OBJECT_NOT_FOUND (0x80bb0001) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={SessionMachine} aText={No storage device attached to device slot 0 on port 2 of controller 'Hard Disk Controller'}, preserve=false aResultDetail=0
00:00:09.351994          WARNING [COM]: aRC=E_FAIL (0x80004005) aIID={e54f6256-97a7-4947-8a78-10c013ddf4b8} aComponent={HostWrap} aText={Could not load the Host USB Proxy Service (VERR_FILE_NOT_FOUND).  The service might not be installed on the host computer}, preserve=true aResultDetail=0
00:00:09.352137          WARNING [COM]: aRC=E_FAIL (0x80004005) aIID={e54f6256-97a7-4947-8a78-10c013ddf4b8} aComponent={HostWrap} aText={Could not load the Host USB Proxy Service (VERR_FILE_NOT_FOUND).  The service might not be installed on the host computer}, preserve=true aResultDetail=0
00:00:09.354815          ERROR [COM]: aRC=E_FAIL (0x80004005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={SessionMachine} aText={This machine does not have any snapshots}, preserve=false aResultDetail=0
00:00:09.608895          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:09.621774          Launched VM: 1198088256 pid: 6848 (0x1ac0) frontend: headless name: boinc_05000aedbde784d5
00:00:10.778496 Watcher  ERROR [COM]: aRC=E_FAIL (0x80004005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The virtual machine 'boinc_05000aedbde784d5' has terminated unexpectedly during startup with exit code 1 (0x1).  More details may be available in 'C:\ProgramData\BOINC\slots\0\boinc_05000aedbde784d5\Logs\VBoxHardening.log'}, preserve=false aResultDetail=0
00:00:10.910687          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:10.912963          ERROR [COM]: aRC=E_FAIL (0x80004005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={SessionMachine} aText={This machine does not have any snapshots}, preserve=false aResultDetail=0
00:00:10.992109          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:10.994708          Saving settings file "C:\ProgramData\BOINC\slots\0\boinc_05000aedbde784d5\boinc_05000aedbde784d5.vbox" with version "1.19-windows"
00:00:10.998046          Finished saving settings file "C:\ProgramData\BOINC\slots\0\boinc_05000aedbde784d5\boinc_05000aedbde784d5.vbox"
00:00:11.260570          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:11.261069          ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={300763af-5d6b-46e6-aa96-273eac15538a} aComponent={MachineWrap} aText={The object functionality is limited}, preserve=false aResultDetail=0
00:00:11.261230          Saving settings file "C:\Users\g.morange\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:11.263757          Finished saving settings file "C:\Users\g.morange\.VirtualBox\VirtualBox.xml"
00:00:11.263924          Saving settings file "C:\Users\g.morange\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:11.266325          Finished saving settings file "C:\Users\g.morange\.VirtualBox\VirtualBox.xml"
00:00:11.267276 DeleteVM Saving settings file "C:\Users\g.morange\.VirtualBox\VirtualBox.xml" with version "1.12-windows"
00:00:11.269630 DeleteVM Finished saving settings file "C:\Users\g.morange\.VirtualBox\VirtualBox.xml"
00:00:16.286636 main     VirtualBox: object deletion starts
00:00:16.287401 main     HostDnsMonitor: shutting down ...
00:00:16.287520 main     HostDnsMonitor: shut down
00:00:16.288179 Watcher  ERROR [COM]: aRC=E_ACCESSDENIED (0x80070005) aIID={7682d5eb-f00e-44f1-8ca2-99d08b1cd607} aComponent={VirtualBoxWrap} aText={The object is not ready}, preserve=false aResultDetail=0
00:00:16.288464 main     VirtualBox: object deleted

    VM Execution Log:


    VM Startup Log:


    VM Trace Log:

teraddress=""
teleporterpassword=""
tracing-enabled="off"
tracing-allow-vm-access="off"
tracing-config=""
autostart-enabled="off"
autostart-delay=0
defaultfrontend=""
vmprocpriority="default"
natnet1="nat"
macaddress1="080027AE2E18"
cableconnected1="on"
nic1="nat"
nictype1="82540EM"
nicspeed1="0"
mtu="0"
sockSnd="64"
sockRcv="64"
tcpWndSnd="64"
tcpWndRcv="64"
nic2="none"
nic3="none"
nic4="none"
nic5="none"
nic6="none"
nic7="none"
nic8="none"
hidpointing="ps2mouse"
hidkeyboard="ps2kbd"
uart1="off"
uart2="off"
uart3="off"
uart4="off"
lpt1="off"
lpt2="off"
audio="default"
audio_out="off"
audio_in="off"
clipboard="disabled"
draganddrop="disabled"
vrde="off"
usb="off"
ehci="off"
xhci="off"
recording_enabled="off"
recording_screens=1
 rec_screen0
rec_screen_enabled="on"
rec_screen_id=0
rec_screen_video_enabled="on"
rec_screen_audio_enabled="off"
rec_screen_dest="File"
rec_screen_dest_filename="C:\\ProgramData\\BOINC\\slots\\0\\boinc_05000aedbde784d5\\boinc_05000aedbde784d5-screen0.webm"
rec_screen_opts="vc_enabled=true,ac_enabled=false,ac_profile=med"
rec_screen_video_res_xy="1024x768"
rec_screen_video_rate_kbps=512
rec_screen_video_fps=25
description="Theory_2914-4749516-23_1"
GuestMemoryBalloon=0

2025-06-06 16:21:46 (14460): 
Command: VBoxManage -q modifyvm "boinc_05000aedbde784d5" --nic1 nat --nic-type1 "virtio" --cable-connected1 off --nat-dns-proxy1 on 
Exit Code: 0
Output:

2025-06-06 16:21:47 (14460): 
Command: VBoxManage -q modifyvm "boinc_05000aedbde784d5" --cable-connected1 on 
Exit Code: 0
Output:

2025-06-06 16:21:47 (14460): 
Command: VBoxManage -q modifyvm "boinc_05000aedbde784d5" --usb off 
Exit Code: 0
Output:

2025-06-06 16:21:47 (14460): 
Command: VBoxManage -q modifyvm "boinc_05000aedbde784d5" --uart1 off --uart2 off 
Exit Code: 0
Output:

2025-06-06 16:21:47 (14460): 
Command: VBoxManage -q modifyvm "boinc_05000aedbde784d5" --lpt1 off --lpt2 off 
Exit Code: 0
Output:

2025-06-06 16:21:48 (14460): 
Command: VBoxManage -q modifyvm "boinc_05000aedbde784d5" --audio-enabled off 
Exit Code: 0
Output:

2025-06-06 16:21:48 (14460): 
Command: VBoxManage -q modifyvm "boinc_05000aedbde784d5" --clipboard disabled 
Exit Code: 0
Output:

2025-06-06 16:21:48 (14460): 
Command: VBoxManage -q modifyvm "boinc_05000aedbde784d5" --draganddrop disabled 
Exit Code: 0
Output:

2025-06-06 16:21:48 (14460): 
Command: VBoxManage -q storagectl "boinc_05000aedbde784d5" --name "Hard Disk Controller" --add "sata" --controller "IntelAHCI" --hostiocache off --portcount 3
Exit Code: 0
Output:

2025-06-06 16:21:49 (14460): 
Command: VBoxManage -q showhdinfo "C:\ProgramData\BOINC/projects/lhcathome.cern.ch_lhcathome/Theory_2025_04_17_prod.vdi" 
Exit Code: 0
Output:
UUID:           b1b25507-41e2-4ead-9ca8-6f5e1c8e2ce4
Parent UUID:    base
State:          created
Type:           multiattach
Location:       C:\ProgramData\BOINC\projects\lhcathome.cern.ch_lhcathome\Theory_2025_04_17_prod.vdi
Storage format: VDI
Format variant: dynamic default
Capacity:       10240 MBytes
Size on disk:   2451 MBytes
Encryption:     disabled
Property:       AllocationBlockSize=1048576

2025-06-06 16:21:49 (14460): 
Command: VBoxManage -q storageattach "boinc_05000aedbde784d5" --storagectl "Hard Disk Controller" --port 0 --device 0 --type hdd --mtype multiattach --medium "C:\ProgramData\BOINC/projects/lhcathome.cern.ch_lhcathome/Theory_2025_04_17_prod.vdi" 
Exit Code: -2135228409
Output:
VBoxManage.exe: error: Cannot attach medium 'C:\ProgramData\BOINC\projects\lhcathome.cern.ch_lhcathome\Theory_2025_04_17_prod.vdi': the media type 'MultiAttach' can only be attached to machines that were created with VirtualBox 4.0 or later
VBoxManage.exe: error: Details: code VBOX_E_INVALID_OBJECT_STATE (0x80bb0007), component SessionMachine, interface IMachine, callee IUnknown
VBoxManage.exe: error: Context: "AttachDevice(Bstr(pszCtl).raw(), port, device, DeviceType_HardDisk, pMedium2Mount)" at line 785 of file VBoxManageStorageController.cpp

2025-06-06 16:21:49 (14460): 
Command: VBoxManage -q showhdinfo "C:\ProgramData\BOINC/projects/lhcathome.cern.ch_lhcathome/Theory_2025_04_17_prod.vdi" 
Exit Code: 0
Output:
UUID:           b1b25507-41e2-4ead-9ca8-6f5e1c8e2ce4
Parent UUID:    base
State:          created
Type:           multiattach
Location:       C:\ProgramData\BOINC\projects\lhcathome.cern.ch_lhcathome\Theory_2025_04_17_prod.vdi
Storage format: VDI
Format variant: dynamic default
Capacity:       10240 MBytes
Size on disk:   2451 MBytes
Encryption:     disabled
Property:       AllocationBlockSize=1048576

2025-06-06 16:21:49 (14460): 
Command: VBoxManage -q closemedium disk "C:\ProgramData\BOINC\projects\lhcathome.cern.ch_lhcathome\Theory_2025_04_17_prod.vdi" 
Exit Code: 0
Output:

2025-06-06 16:21:50 (14460): 
Command: VBoxManage -q showhdinfo "C:\ProgramData\BOINC/projects/lhcathome.cern.ch_lhcathome/Theory_2025_04_17_prod.vdi" 
Exit Code: 0
Output:
UUID:           b1b25507-41e2-4ead-9ca8-6f5e1c8e2ce4
Parent UUID:    base
State:          created
Type:           normal (base)
Location:       C:\ProgramData\BOINC\projects\lhcathome.cern.ch_lhcathome\Theory_2025_04_17_prod.vdi
Storage format: VDI
Format variant: dynamic default
Capacity:       10240 MBytes
Size on disk:   2451 MBytes
Encryption:     disabled
Property:       AllocationBlockSize=1048576

2025-06-06 16:21:50 (14460): 
Command: VBoxManage -q storageattach "boinc_05000aedbde784d5" --storagectl "Hard Disk Controller" --port 0 --device 0 --type hdd --medium "C:\ProgramData\BOINC/projects/lhcathome.cern.ch_lhcathome/Theory_2025_04_17_prod.vdi" 
Exit Code: 0
Output:

2025-06-06 16:21:50 (14460): 
Command: VBoxManage -q storageattach "boinc_05000aedbde784d5" --storagectl "Hard Disk Controller" --port 0 --device 0 --type hdd --medium none 
Exit Code: 0
Output:

2025-06-06 16:21:51 (14460): 
Command: VBoxManage -q storageattach "boinc_05000aedbde784d5" --storagectl "Hard Disk Controller" --port 0 --device 0 --type hdd --mtype multiattach --medium "C:\ProgramData\BOINC/projects/lhcathome.cern.ch_lhcathome/Theory_2025_04_17_prod.vdi" 
Exit Code: 0
Output:

2025-06-06 16:21:51 (14460): 
Command: VBoxManage -q storageattach "boinc_05000aedbde784d5" --storagectl "Hard Disk Controller" --port 1 --device 0 --type dvddrive --medium "C:\Program Files\Oracle\VirtualBox/VBoxGuestAdditions.iso" 
Exit Code: 0
Output:

2025-06-06 16:21:51 (14460): 
Command: VBoxManage -q bandwidthctl "boinc_05000aedbde784d5" add "boinc_05000aedbde784d5_net" --type network --limit 1024G 
Exit Code: 0
Output:

2025-06-06 16:21:51 (14460): 
Command: VBoxManage -q modifyvm "boinc_05000aedbde784d5" --natpf1 ",tcp,127.0.0.1,62155,,80" 
Exit Code: 0
Output:

2025-06-06 16:21:52 (14460): 
Command: VBoxManage -q list extpacks
Exit Code: 0
Output:
Extension Packs: 0

2025-06-06 16:21:52 (14460): 
Command: VBoxManage -q sharedfolder add "boinc_05000aedbde784d5" --name "shared" --hostpath "C:\ProgramData\BOINC\slots\0/shared"
Exit Code: 0
Output:

2025-06-06 16:21:53 (14460): 
Command: VBoxManage -q startvm "boinc_05000aedbde784d5" --type headless
Exit Code: 1
Output:
VBoxManage.exe: error: The virtual machine 'boinc_05000aedbde784d5' has terminated unexpectedly during startup with exit code 1 (0x1).  More details may be available in 'C:\ProgramData\BOINC\slots\0\boinc_05000aedbde784d5\Logs\VBoxHardening.log'
VBoxManage.exe: error: Details: code E_FAIL (0x80004005), component MachineWrap, interface IMachine
Waiting for VM "boinc_05000aedbde784d5" to power on...

2025-06-06 16:21:54 (14460): 
Command: VBoxManage -q snapshot "boinc_05000aedbde784d5" list 
Exit Code: -108
Output:
This machine does not have any snapshots

2025-06-06 16:21:54 (14460): 
Command: VBoxManage -q bandwidthctl "boinc_05000aedbde784d5" remove "boinc_05000aedbde784d5_net" 
Exit Code: 0
Output:

2025-06-06 16:21:54 (14460): 
Command: VBoxManage -q unregistervm "boinc_05000aedbde784d5" --delete 
Exit Code: 0
Output:
0%...10%...20%...30%...40%...50%...60%...70%...80%...90%...100%

2025-06-06 16:22:00 (14460): called boinc_finish(1)

</stderr_txt>
]]>


©2025 CERN